There are really two important special deals when you plan to keep it stock appearing and running factory iron heads with big open chambers: Keep the static compression down around 9.5:1 which means using a dished piston; and get yourself a custom ground camshaft. I don't see you staying within the $6K budget limit using any decent shop and expecting to pick it up ready to fire. You will need the stroker parts, plus the heads completely gone through, then the custom cam, an aftermarket set of rockers, new pushrods, etc. etc. Add another $500-1000 for an un-fired combo depending on the cam choice, and another $1K on top of that if you want it warranteed and dyno'd (I would recommend that).